The Kjeragbolten boulder on the mountain Kjerag in Rogaland county, Norway

Between a rock and a hard place. Norway's Kjeragbolten boulder

If you have nerves of steel, you'd enjoy the precarious, one-of-a-kind photo op that is the Kjeragbolten boulder. Visitors climb up Kjerag, a mountain on the southwest coast of Norway, for the chance to clamber onto the stranded rock and have their daredevil pic snapped for posterity. Indeed, Kjeragbolten is so popular that you might have to wait up to an hour for your turn—plenty of time for second thoughts and jitters.

So how did Kjeragbolten become wedged in a crevice on Kjerag, with a clear 791-foot drop below? Experts say that after millions of years of glacial activity the ice finally receded to the valley, leaving the famous rock in the mountain's grip. Today the piece of geological history invites brave adventurers and steady-handed photographers. If adrenaline rushes aren't your thing, don't worry: The mountain itself offers perfectly safe, breathtaking views of the valley and fjord below.